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Rico-Cambron TY, Bello-Bello E, Martínez O, Herrera-Estrella L. A non-invasive method to predict drought survival in Arabidopsis using quantum yield under light conditions. PLANT METHODS 2023; 19:127. [PMID: 37968652 PMCID: PMC10647164 DOI: 10.1186/s13007-023-01107-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/21/2023] [Accepted: 11/10/2023] [Indexed: 11/17/2023]
Abstract
BACKGROUND Survival rate (SR) is frequently used to compare drought tolerance among plant genotypes. While a variety of techniques for evaluating the stress status of plants under drought stress conditions have been developed, determining the critical point for the recovery irrigation to evaluate plant SR often relies directly on a qualitative inspection by the researcher or on the employment of complex and invasive techniques that invalidate the subsequent use of the tested individuals. RESULTS Here, we present a simple, instantaneous, and non-invasive method to estimate the survival probability of Arabidopsis thaliana plants after severe drought treatments. The quantum yield (QY), or efficiency of photosystem II, was monitored in darkness (Fv/Fm) and light (Fv'/Fm') conditions in the last phase of the drought treatment before recovery irrigation. We found a high correlation between a plant's Fv'/Fm' value before recovery irrigation and its survival phenotype seven days after, allowing us to establish a threshold between alive and dead plants in a calibration stage. This correlation was maintained in the Arabidopsis accessions Col-0, Ler-0, C24, and Kondara under the same conditions. Fv'/Fm' was then applied as a survival predictor to compare the drought tolerance of transgenic lines overexpressing the transcription factors ATAF1 and PLATZ1 with the Col-0 control. CONCLUSIONS The results obtained in this work demonstrate that the chlorophyll a fluorescence parameter Fv'/Fm' can be used as a survival predictor that gives a numerical estimate of the Arabidopsis drought SR before recovery irrigation. The procedure employed to get the Fv'/Fm' measurements is fast, non-destructive, and requires inexpensive and easy-to-handle equipment. Fv'/Fm' as a survival predictor can be used to offer an overview of the photosynthetic state of the tested plants and determine more accurately the best timing for rewatering to assess the SR, especially when the symptoms of severe dehydration between genotypes are not contrasting enough to identify a difference visually.
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Affiliation(s)
- Thelma Y Rico-Cambron
- National Laboratory of Genomics for Biodiversity (LANGEBIO), Unit of Advanced Genomics, CINVESTAV, Irapuato, Guanajuato, 36824, Mexico
| | - Elohim Bello-Bello
- National Laboratory of Genomics for Biodiversity (LANGEBIO), Unit of Advanced Genomics, CINVESTAV, Irapuato, Guanajuato, 36824, Mexico
- Plant Molecular and Cellular Biology Laboratory, Salk Institute for Biological Studies, La Jolla, CA, 92037, USA
| | - Octavio Martínez
- National Laboratory of Genomics for Biodiversity (LANGEBIO), Unit of Advanced Genomics, CINVESTAV, Irapuato, Guanajuato, 36824, Mexico
| | - Luis Herrera-Estrella
- National Laboratory of Genomics for Biodiversity (LANGEBIO), Unit of Advanced Genomics, CINVESTAV, Irapuato, Guanajuato, 36824, Mexico.
- Department of Plant and Soil Science, Institute of Genomics for Crop Abiotic Stress Tolerance, Texas Tech University, Lubbock, TX, 79409, USA.
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Qiu CW, Ma Y, Wang QQ, Fu MM, Li C, Wang Y, Wu F. Barley HOMOCYSTEINE METHYLTRANSFERASE 2 confers drought tolerance by improving polyamine metabolism. PLANT PHYSIOLOGY 2023; 193:389-409. [PMID: 37300541 DOI: 10.1093/plphys/kiad333] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/16/2023] [Revised: 04/25/2023] [Accepted: 05/18/2023] [Indexed: 06/12/2023]
Abstract
Drought stress poses a serious threat to crop production worldwide. Genes encoding homocysteine methyltransferase (HMT) have been identified in some plant species in response to abiotic stress, but its molecular mechanism in plant drought tolerance remains unclear. Here, transcriptional profiling, evolutionary bioinformatics, and population genetics were conducted to obtain insight into the involvement of HvHMT2 from Tibetan wild barley (Hordeum vulgare ssp. agriocrithon) in drought tolerance. We then performed genetic transformation coupled with physio-biochemical dissection and comparative multiomics approaches to determine the function of this protein and the underlying mechanism of HvHMT2-mediated drought tolerance. HvHMT2 expression was strongly induced by drought stress in tolerant genotypes in a natural Tibetan wild barley population and contributed to drought tolerance through S-adenosylmethionine (SAM) metabolism. Overexpression of HvHMT2 promoted HMT synthesis and efficiency of the SAM cycle, leading to enhanced drought tolerance in barley through increased endogenous spermine and less oxidative damage and growth inhibition, thus improving water status and final yield. Disruption of HvHMT2 expression led to hypersensitivity under drought treatment. Application of exogenous spermine reduced accumulation of reactive oxygen species (ROS), which was increased by exogenous mitoguazone (inhibitor of spermine biosynthesis), consistent with the association of HvHMT2-mediated spermine metabolism and ROS scavenging in drought adaptation. Our findings reveal the positive role and key molecular mechanism of HvHMT2 in drought tolerance in plants, providing a valuable gene not only for breeding drought-tolerant barley cultivars but also for facilitating breeding schemes in other crops in a changing global climate.
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Affiliation(s)
- Cheng-Wei Qiu
- Department of Agronomy, College of Agriculture and Biotechnology, Zijingang Campus, Zhejiang University, Hangzhou 310058, P.R. China
- Jiangsu Co-Innovation Center for Modern Production Technology of Grain Crops, Yangzhou University, Yangzhou 225009, P.R. China
| | - Yue Ma
- Department of Agronomy, College of Agriculture and Biotechnology, Zijingang Campus, Zhejiang University, Hangzhou 310058, P.R. China
| | - Qing-Qing Wang
- Department of Agronomy, College of Agriculture and Biotechnology, Zijingang Campus, Zhejiang University, Hangzhou 310058, P.R. China
- Jiangsu Co-Innovation Center for Modern Production Technology of Grain Crops, Yangzhou University, Yangzhou 225009, P.R. China
| | - Man-Man Fu
- Department of Agronomy, College of Agriculture and Biotechnology, Zijingang Campus, Zhejiang University, Hangzhou 310058, P.R. China
| | - Chengdao Li
- Western Barley Genetics Alliance, State Agricultural Biotechnology Centre, College of Science, Health, Engineering and Education, Murdoch University, Murdoch, WA 6150, Australia
| | - Yizhou Wang
- Department of Agronomy, College of Agriculture and Biotechnology, Zijingang Campus, Zhejiang University, Hangzhou 310058, P.R. China
| | - Feibo Wu
- Department of Agronomy, College of Agriculture and Biotechnology, Zijingang Campus, Zhejiang University, Hangzhou 310058, P.R. China
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Kamruzzaman M, Beyene MA, Siddiqui MN, Ballvora A, Léon J, Naz AA. Pinpointing genomic loci for drought-induced proline and hydrogen peroxide accumulation in bread wheat under field conditions. BMC PLANT BIOLOGY 2022; 22:584. [PMID: 36513990 PMCID: PMC9746221 DOI: 10.1186/s12870-022-03943-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 08/13/2022] [Accepted: 11/14/2022] [Indexed: 06/17/2023]
Abstract
BACKGROUND Proline (Pro) and hydrogen peroxide (H2O2) play a critical role in plants during drought adaptation. Genetic mapping for drought-induced Pro and H2O2 production under field conditions is very limited in crop plants since their phenotyping with large populations is labor-intensive. A genome-wide association study (GWAS) of a diversity panel comprised of 184 bread wheat cultivars grown in natural field (control) and rain-out shelter (drought) environments was performed to identify candidate loci and genes regulating Pro and H2O2 accumulation induced by drought. RESULTS The GWAS identified top significant marker-trait associations (MTAs) on 1A and 2A chromosomes, respectively for Pro and H2O2 in response to drought. Similarly, MTAs for stress tolerance index (STI) of Pro and H2O2 were identified on 5B and 1B chromosomes, respectively. Total 143 significant MTAs were identified including 36 and 71 were linked to drought and 2 and 34 were linked to STI for Pro and H2O2, respectively. Next, linkage disequilibrium analysis revealed minor alleles of significant single-markers and haplotypes were associated with higher Pro and H2O2 accumulation under drought. Several putative candidate genes for Pro and H2O2 content encode proteins with kinase, transporter or protein-binding activities. CONCLUSIONS The identified genetic factors associated with Pro and H2O2 biosynthesis underlying drought adaptation lay a fundamental basis for functional studies and future marker-assisted breeding programs.
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Affiliation(s)
- Mohammad Kamruzzaman
- Institute of Crop Science and Resource Conservation (INRES)-Plant Breeding and Biotechnology, University of Bonn, Bonn, Germany
- Plant Breeding Division, Bangladesh Institute of Nuclear Agriculture (BINA), Mymensingh-2202, Bangladesh
| | - Mekides Abebe Beyene
- Institute of Crop Science and Resource Conservation (INRES)-Plant Breeding and Biotechnology, University of Bonn, Bonn, Germany
| | - Md Nurealam Siddiqui
- Institute of Crop Science and Resource Conservation (INRES)-Plant Breeding and Biotechnology, University of Bonn, Bonn, Germany
- Department of Biochemistry and Molecular Biology, Bangabandhu Sheikh Mujibur Rahman Agricultural University, Gazipur 1706, Bangladesh
| | - Agim Ballvora
- Institute of Crop Science and Resource Conservation (INRES)-Plant Breeding and Biotechnology, University of Bonn, Bonn, Germany
| | - Jens Léon
- Institute of Crop Science and Resource Conservation (INRES)-Plant Breeding and Biotechnology, University of Bonn, Bonn, Germany
- Field Lab Campus Klein-Altendorf, University of Bonn, Bonn, Germany
| | - Ali Ahmad Naz
- Institute of Crop Science and Resource Conservation (INRES)-Plant Breeding and Biotechnology, University of Bonn, Bonn, Germany.
- Department of Plant Breeding, University of Applied Sciences, Osnabrueck, Osnabrueck, Germany.
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Selenium-induced modulations in growth, productivity and physiochemical responses to water deficiency in Quinoa (Chenopodium quinoa) grown in sandy soil. BIOCATALYSIS AND AGRICULTURAL BIOTECHNOLOGY 2022. [DOI: 10.1016/j.bcab.2022.102449] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
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A Framework on Analyzing Long-Term Drought Changes and Its Influential Factors Based on the PDSI. ATMOSPHERE 2022. [DOI: 10.3390/atmos13071151] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
Drought is one of the most frequent and most widespread natural disasters worldwide, significantly impacting agricultural production and the ecological environment. An investigation of long-term drought changes and its influencing factors provides not only an understanding of historical droughts but also a scientific basis for the protection of future water resources. This study investigated the temporal characteristics of drought in a study site located in the center of Southwest China (SWC) over a 700-year period (AD 1300–2005) using the Palmer Drought Severity Index (PDSI). The linkage between drought and its influencing factors is discussed. An algorithm based on the random forest (RF) method was proposed to analyze the dynamic influence of the factors on drought. We also examined the linkages between the demise of two dynasties and historical drought events. The results showed that the study site was a drought-prone area in the study period and experienced a non-significant drying trend in all centuries, except for the 17th century; a total of 232 droughts were detected in the study site from AD 1300–2005. The wavelet spectrum of the PDSI series showed the existence of 4-, 8-, 16-, 32-, and 128-year-periods. A strong correlation existed between the sunspot numbers and the PDSI. The correlation of the period between the PDSI and El Niño-Southern Oscillation (ENSO) series in the same frequency domain was weak, while the ENSO exhibited a strong interaction with the PDSI in some time periods. The Pacific Decadal Oscillation (PDO) and PDSI had no resonance period in the low-frequency region, but there was a period of 80–130 years in the high-frequency region. The relative rates of influence of the ENSO, sunspot numbers, and PDO during AD 1700–1996 were 38.40%, 31.81%, and 29.8%, respectively. However, the mechanism of the interaction between droughts and the influential factors is complex, and the dominant factor changed over time. The analysis of long-term drought changes based on the PDSI series may provide clues to understand the development of historical events.
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Climate change and modernization drive structural realignments in European grain production. Sci Rep 2022; 12:7374. [PMID: 35513405 PMCID: PMC9072400 DOI: 10.1038/s41598-022-10670-6] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2021] [Accepted: 04/11/2022] [Indexed: 11/09/2022] Open
Abstract
Charting the long-term trends in European wheat and maize yields and harvested areas and the relation of yields to climatic and economic drivers, two profound spatial processes become apparent. One consequence of the relatively late modernization of Eastern Europe has been to shift the focus of grain production from West to East. The warming trend prevailing over the past decades in the summer and winter seasons has been accompanied by a South to North shift in the harvested areas. The combination of these two processes has meant that the north-eastern sector of the European grain chessboard has emerged as the main beneficiary. There, the relatively low sensitivity of cereals to climatic change plus high economic growth rates have been accompanied by the most dynamic increases in cereal yields on the continent. As a result, a modern version of the 3000 year-old grain distribution system of the Ancient World is being restored before our eyes. One noteworthy finding is that increasing January–March temperatures have had a significant positive impact on wheat yields from Northern to South-Eastern Europe, and this is, at least in part, compensating for the negative impact of summer warming.
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Li L, Yi H. Enhancement of drought tolerance in Arabidopsis plants induced by sulfur dioxide. ECOTOXICOLOGY (LONDON, ENGLAND) 2022; 31:637-648. [PMID: 35296952 DOI: 10.1007/s10646-022-02530-w] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Accepted: 02/21/2022] [Indexed: 06/14/2023]
Abstract
Sulfur dioxide (SO2) is a common air pollutant that has multiple effects on plants. In the present study, the improvement of drought tolerance in Arabidopsis plants by SO2 fumigation was investigated. The results showed that pre-exposure to 30 mg/m3 SO2 for 72 h could reduce water loss, stomatal conductance (Gs) and the transpiration rate (Tr) but increased the net photosynthetic rate (Pn), water use efficiency (iWUE) and photosynthetic pigment contents under drought conditions. The activities of superoxide dismutase (SOD) and peroxidase (POD) were significantly increased, while the contents of hydrogen peroxide (H2O2) and malondialdehyde (MDA) were decreased in SO2-pretreated Arabidopsis plants under drought stress. Additionally, the activity of o-acetylserine(thio)lyase (OASTL) and the content of cysteine (Cys), the rate-limiting enzyme and the first organic product of sulfur assimilation, were significantly increased in drought-stressed plants after SO2 pretreatment, along with increases in other thiol-containing compounds, such as glutathione (GSH) and nonprotein thiol (NPT). Meanwhile, SO2 pre-exposure induced a higher level of proline accumulation, with increased activity of proline synthase P5CS and decreased activity of proline dehydrogenase ProDH. Consistent with the changes in enzyme activity, their corresponding gene expression patterns were different after SO2 treatment. Overall, the enhanced drought tolerance afforded by SO2 might be related to the improvement of plant photosynthesis, antioxidant defense, sulfur assimilation and osmotic adjustment. These findings provide new insights into the role of SO2 in plant adaptation to environmental stress.
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Affiliation(s)
- Lijuan Li
- School of Life Science, Shanxi University, Taiyuan, 030006, Shanxi Province, China
| | - Huilan Yi
- School of Life Science, Shanxi University, Taiyuan, 030006, Shanxi Province, China.
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Santini M, Noce S, Antonelli M, Caporaso L. Complex drought patterns robustly explain global yield loss for major crops. Sci Rep 2022; 12:5792. [PMID: 35388057 PMCID: PMC8986840 DOI: 10.1038/s41598-022-09611-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2021] [Accepted: 03/24/2022] [Indexed: 11/08/2022] Open
Abstract
Multi-purpose crops as maize, rice, soybean, and wheat are key in the debate concerning food, land, water and energy security and sustainability. While strong evidence exists on the effects of climate variability on the production of these crops, so far multifaceted attributes of droughts-magnitude, frequency, duration, and timing-have been tackled mainly separately, for a limited part of the cropping season, or over small regions. Here, a more comprehensive assessment is provided on how droughts with their complex patterns-given by their compound attributes-are consistently related to negative impacts on crop yield on a global scale. Magnitude and frequency of both climate and yield variability are jointly analysed from 1981 to 2016 considering multiscale droughts, i.e., dry conditions occurring with different durations and timings along the whole farming season, through two analogous and standardized indicators enabling comparison among crops, countries, and years. Mainly winter wheat and then spring wheat, soybean and the main maize's season reveal high susceptibility of yield under more complex drought patterns than previously assessed. The second maize's season and rice present less marked and more uncertain results, respectively. Overall, southern and eastern Europe, the Americas and sub-Saharan Africa presents multi-crop susceptibility, with eastern Europe, Middle East and Central Asia appearing critical regions for the most vulnerable crop, which is wheat. Finally, yield losses for wheat and soybean clearly worsen when moving from moderate to extreme multiscale droughts.
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Affiliation(s)
- Monia Santini
- Impacts on Agriculture, Forests and Ecosystem Services (IAFES) Division, Foundation Euro-Mediterranean Center on Climate Change (CMCC), 01100, Viterbo, Italy.
| | - Sergio Noce
- Impacts on Agriculture, Forests and Ecosystem Services (IAFES) Division, Foundation Euro-Mediterranean Center on Climate Change (CMCC), 01100, Viterbo, Italy
| | - Marta Antonelli
- Impacts on Agriculture, Forests and Ecosystem Services (IAFES) Division, Foundation Euro-Mediterranean Center on Climate Change (CMCC), 01100, Viterbo, Italy
- Barilla Center for Food & Nutrition (BCFN) Foundation, 43121, Parma, Italy
| | - Luca Caporaso
- Impacts on Agriculture, Forests and Ecosystem Services (IAFES) Division, Foundation Euro-Mediterranean Center on Climate Change (CMCC), 01100, Viterbo, Italy
- European Commission - Joint Research Centre (JRC), 21027, Ispra, Italy
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Multi–Proxy Reconstruction of Drought Variability in China during the Past Two Millennia. WATER 2022. [DOI: 10.3390/w14060858] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Drought imposes serious challenges to ecosystems and societies and has plagued mankind throughout the ages. To understand the long-term trend of drought in China, a series of annual self-calibrating Palmer drought severity indexes (scPDSI), which is a semi-physical drought index based on the land surface water balance, were reconstructed during AD 56~2000. Multi-proxy records of tree-ring width and stalagmite oxygen isotope δ18O were used for this reconstruction, along with random forest regression. The spatiotemporal characteristics of the reconstruction results were analyzed, and comparisons were made with previous studies. Results showed that (1) China witnessed a drought-based state during the past 2000 years (mean value of scPDSI was −0.3151), with an average annual drought area of 85,000 km2; 4 wetting periods, i.e., the Han Dynasty (AD 56~220), the Tang Dynasty (AD 618~907), the Ming Dynasty (AD 1368~1644), and the Qing Dynasty (AD 1644~1912); and 2 drying periods, i.e., the Era of Disunity (AD 221~580) and the Song Dynasty (AD 960~1279). (2) Three different alternating fluctuation dry-wet modes (i.e., interannual, multidecadal, and centennial scales) in China were all significantly (p-value < 0.001) correlated with the amplitude and frequency of temperature in the Northern Hemisphere. (3) According to the spatial models disassembled from the rotated empirical orthogonal function, China was divided into nine dry-wet regions: northwestern China, Xinjiang, southwestern China, southeastern China, the Loess plateau, central China, southwestern Tibet, eastern China, and northeastern China. (4) The random forest (RF) was found to be accurate and stable for the reconstruction of drought variability in China compared with linear regression.
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11
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Biochemical, Physiological, and Molecular Aspects of Ornamental Plants Adaptation to Deficit Irrigation. HORTICULTURAE 2021. [DOI: 10.3390/horticulturae7050107] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
There is increasing concern regarding global warming and its severe impact on the farming sector and food security. Incidences of extreme weather conditions are becoming more and more frequent, posing plants to stressful conditions, such as flooding, drought, heat, or frost etc. Especially for arid lands, there is a tug-of-war between keeping high crop yields and increasing water use efficiency of limited water resources. This difficult task can be achieved through the selection of tolerant water stress species or by increasing the tolerance of sensitive species. In this scenario, it is important to understand the response of plants to water stress. So far, the response of staple foods and vegetable crops to deficit irrigation is well studied. However, there is lack of literature regarding the responses of ornamental plants to water stress conditions. Considering the importance of this ever-growing sector for the agricultural sector, this review aims to reveal the defense mechanisms and the involved morpho-physiological, biochemical, and molecular changes in ornamental plant’s responses to deficit irrigation.
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Marçal DMS, Avila RT, Quiroga-Rojas LF, de Souza RPB, Gomes Junior CC, Ponte LR, Barbosa ML, Oliveira LA, Martins SCV, Ramalho JDC, DaMatta FM. Elevated [CO 2] benefits coffee growth and photosynthetic performance regardless of light availability. PLANT PHYSIOLOGY AND BIOCHEMISTRY : PPB 2021; 158:524-535. [PMID: 33293205 DOI: 10.1016/j.plaphy.2020.11.042] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/18/2020] [Accepted: 11/24/2020] [Indexed: 06/12/2023]
Abstract
Despite being evolved in shaded environments, most coffee (Coffea arabica L.) is cultivated worldwide under sparse shade or at full sunlight. Coffee is ranked as greatly responsive to climate change (CC), and shading has been considered an important management strategy for mitigating the harmful CC outcomes on the crop. However, there is no information on the effects of enhanced [CO2] (eCa) on coffee performance in response to light availability. Here, we examined how carbon assimilation and use are affected by eCa in combination with contrasting light levels. For that, greenhouse-grown plants were submitted to varying light levels (16 or 7.5 mol photons m-2 day-1) and [CO2] (ca. 380 or 740 μmol mol-1 air) over six months. We demonstrated that both high light and eCa improved growth and photosynthetic performance, independently. Despite marginal alterations in biomass partitioning, some allometric changes, such as higher root biomass-to-total leaf area and lower leaf area ratio under the combination of eCa and high light were found. Stimulation of photosynthetic rates by eCa occurred with no direct effect on stomatal and mesophyll conductances, and no signs of photosynthetic down-regulation were found irrespective of treatments. Particularly at high light, eCa led to decreases in both photorespiration rates and oxidative pressure. Overall, our novel findings suggest that eCa could tandemly act with shading to mitigate the harmful CC effects on coffee sustainability.
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Affiliation(s)
- Dinorah M S Marçal
- Departamento de Biologia Vegetal, Universidade Federal de Viçosa, 36570-900, Viçosa, MG, Brazil.
| | - Rodrigo T Avila
- Departamento de Biologia Vegetal, Universidade Federal de Viçosa, 36570-900, Viçosa, MG, Brazil.
| | | | - Raylla P B de Souza
- Departamento de Biologia Vegetal, Universidade Federal de Viçosa, 36570-900, Viçosa, MG, Brazil.
| | - Carlos C Gomes Junior
- Departamento de Biologia Vegetal, Universidade Federal de Viçosa, 36570-900, Viçosa, MG, Brazil.
| | - Lucas R Ponte
- Departamento de Biologia Vegetal, Universidade Federal de Viçosa, 36570-900, Viçosa, MG, Brazil.
| | - Marcela L Barbosa
- Departamento de Biologia Vegetal, Universidade Federal de Viçosa, 36570-900, Viçosa, MG, Brazil.
| | - Leonardo A Oliveira
- Departamento de Biologia Vegetal, Universidade Federal de Viçosa, 36570-900, Viçosa, MG, Brazil.
| | - Samuel C V Martins
- Departamento de Biologia Vegetal, Universidade Federal de Viçosa, 36570-900, Viçosa, MG, Brazil.
| | - José D C Ramalho
- PlantStress & Biodiversity Lab, Centro de Estudos Florestais (CEF), Dept. Recursos Naturais, Ambiente e Território (DRAT), Instituto Superior de Agronomia (ISA), Universidade de Lisboa (ULisboa), Quinta do Marquês, Av. da República, 2784-505, Oeiras, Portugal; Unidade de Geobiociências, Geoengenharias e Geotecnologias (GeoBioTec), Faculdade de Ciências e Tecnologia (FCT), Universidade NOVA de Lisboa (UNL), Monte de Caparica, 2829-516, Caparica, Portugal.
| | - Fábio M DaMatta
- Departamento de Biologia Vegetal, Universidade Federal de Viçosa, 36570-900, Viçosa, MG, Brazil.
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Al-Yasi H, Attia H, Alamer K, Hassan F, Ali E, Elshazly S, Siddique KHM, Hessini K. Impact of drought on growth, photosynthesis, osmotic adjustment, and cell wall elasticity in Damask rose. PLANT PHYSIOLOGY AND BIOCHEMISTRY : PPB 2020; 150:133-139. [PMID: 32142986 DOI: 10.1016/j.plaphy.2020.02.038] [Citation(s) in RCA: 38] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/11/2019] [Accepted: 02/25/2020] [Indexed: 05/21/2023]
Abstract
The response of Damask rose to drought and the underlying mechanisms involved are not known. In this study, vegetative, propagated rose plants were grown under control and water-deficit conditions in a greenhouse at Taïf University, south-west of Saudi Arabia. Control plants were irrigated to field capacity (FC), while water-stressed plants were irrigated to either 50% FC (mild stress) or 25% FC (severe stress). After 60 days, leaf, stem and root fresh and dry weights (g plant-1), photosynthetic activity, leaf water potential (Ψw), leaf water content (WC), apoplastic water fraction (AWF), osmotic potential at full turgor (Ψs100) and turgor loss point (Ψs0), cell wall elasticity, osmotic adjustment (OA), and some solutes (K+, Ca2+, Cl-, proline and soluble carbohydrates) were evaluated. Water stress significantly decreased fresh and dry weights of R. damascena and all photosynthetic parameters, apart from leaf temperature, which increased. Severe water stress (25% FC) resulted in more negative Ψs100 and Ψs0 values than the mild water stress and control. The AWF did not significantly change in response to water stress. The leaf bulk modulus of elasticity (ε) increased from 2.5 MPa under well-watered conditions to 2.82 and 3.5 MPa under mild and severe water stress, respectively. R. damascena experienced OA in response to water stress, which was due to the active accumulation of soluble carbohydrates and, to a lesser degree, proline under mild stress, along with tissue dehydration (passive OA) under severe stress. Overall, we identified two important mechanisms of drought tolerance in R. damascena-osmotic and elastic adjustment-but they could not offer resistance to water stress beyond 25% FC.
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Affiliation(s)
- Hatim Al-Yasi
- Department of Biology, College of Sciences, Taïf University, 21974, Taïf, PO Box 888, Saudi Arabia
| | - Houneida Attia
- Department of Biology, College of Sciences, Taïf University, 21974, Taïf, PO Box 888, Saudi Arabia
| | - Khalid Alamer
- Department of Biology, College of Sciences, Taïf University, 21974, Taïf, PO Box 888, Saudi Arabia; Biology Dep. Science and Arts College-Rabigh Campus, King Abdul-Aziz Univ, Jeddah, Saudi Arabia
| | - Fahmy Hassan
- Department of Biology, College of Sciences, Taïf University, 21974, Taïf, PO Box 888, Saudi Arabia; Horticulture Dep., Faculty of Agric., Tanta University, Egypt
| | - Esmat Ali
- Department of Biology, College of Sciences, Taïf University, 21974, Taïf, PO Box 888, Saudi Arabia
| | - Samir Elshazly
- Department of Biology, College of Sciences, Taïf University, 21974, Taïf, PO Box 888, Saudi Arabia
| | - Kadambot H M Siddique
- The UWA Institute of Agriculture, The University of Western Australia, Perth, WA, 6001, Australia
| | - Kamel Hessini
- Department of Biology, College of Sciences, Taïf University, 21974, Taïf, PO Box 888, Saudi Arabia; Biotechnology Center of Borj-Cedria, The University of Tunis El Manar, Tunis, Tunisia.
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Qiu CW, Liu L, Feng X, Hao PF, He X, Cao F, Wu F. Genome-Wide Identification and Characterization of Drought Stress Responsive microRNAs in Tibetan Wild Barley. Int J Mol Sci 2020; 21:E2795. [PMID: 32316632 PMCID: PMC7216285 DOI: 10.3390/ijms21082795] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2020] [Revised: 04/12/2020] [Accepted: 04/13/2020] [Indexed: 11/16/2022] Open
Abstract
Drought stress is a major obstacle to agricultural production. Tibetan wild barley with rich genetic diversity is useful for drought-tolerant improvement of cereals. MicroRNAs (miRNAs) play critical roles in controlling gene expression in response to various environment perturbations in plants. However, the genome-wide expression profiles of miRNAs and their targets in response to drought stress are largely unknown in wild barley. In this study, a polyethylene glycol (PEG) induced drought stress hydroponic experiment was performed, and the expression profiles of miRNAs from the roots of two contrasting Tibetan wild barley genotypes XZ5 (drought-tolerant) and XZ54 (drought-sensitive), and one cultivated barley Tadmor (drought-tolerant) generated by high-throughput sequencing were compared. There were 69 conserved miRNAs and 1574 novel miRNAs in the dataset of three genotypes under control and drought conditions. Among them, seven conserved miRNAs and 36 novel miRNAs showed significantly genotype-specific expression patterns in response to drought stress. And 12 miRNAs were further regarded as drought tolerant associated miRNAs in XZ5, which mostly participate in gene expression, metabolism, signaling and transportation, suggesting that they and their target genes play important roles in plant drought tolerance. This is the first comparation study on the miRNA transcriptome in the roots of two Tibetan wild barley genotypes differing in drought tolerance and one drought tolerant cultivar in response to PEG treatment. Further results revealed the candidate drought tolerant miRNAs and target genes in the miRNA regulation mechanism in wild barley under drought stress. Our findings provide valuable understandings for the functional characterization of miRNAs in drought tolerance.
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Affiliation(s)
- Cheng-Wei Qiu
- Institute of Crop Science, Department of Agronomy, College of Agriculture and Biotechnology, Zijingang Campus, Zhejiang University, Hangzhou 310058, China; (C.-W.Q.); (X.F.); (P.-F.H.); (X.H.)
| | - Li Liu
- Department of Applied Engineering, Zhejiang Economic and Trade Polytechnic, Hangzhou 310018, China;
| | - Xue Feng
- Institute of Crop Science, Department of Agronomy, College of Agriculture and Biotechnology, Zijingang Campus, Zhejiang University, Hangzhou 310058, China; (C.-W.Q.); (X.F.); (P.-F.H.); (X.H.)
| | - Peng-Fei Hao
- Institute of Crop Science, Department of Agronomy, College of Agriculture and Biotechnology, Zijingang Campus, Zhejiang University, Hangzhou 310058, China; (C.-W.Q.); (X.F.); (P.-F.H.); (X.H.)
| | - Xiaoyan He
- Institute of Crop Science, Department of Agronomy, College of Agriculture and Biotechnology, Zijingang Campus, Zhejiang University, Hangzhou 310058, China; (C.-W.Q.); (X.F.); (P.-F.H.); (X.H.)
| | - Fangbin Cao
- Institute of Crop Science, Department of Agronomy, College of Agriculture and Biotechnology, Zijingang Campus, Zhejiang University, Hangzhou 310058, China; (C.-W.Q.); (X.F.); (P.-F.H.); (X.H.)
| | - Feibo Wu
- Institute of Crop Science, Department of Agronomy, College of Agriculture and Biotechnology, Zijingang Campus, Zhejiang University, Hangzhou 310058, China; (C.-W.Q.); (X.F.); (P.-F.H.); (X.H.)
- Jiangsu Co-Innovation Center for Modern Production Technology of Grain Crops, Yangzhou University, Yangzhou 225009, China
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15
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Li J, Wang Z, Wu X, Guo S, Chen X. Flash droughts in the Pearl River Basin, China: Observed characteristics and future changes. THE SCIENCE OF THE TOTAL ENVIRONMENT 2020; 707:136074. [PMID: 31863997 DOI: 10.1016/j.scitotenv.2019.136074] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/15/2019] [Revised: 12/09/2019] [Accepted: 12/09/2019] [Indexed: 06/10/2023]
Abstract
Heat wave flash drought or precipitation deficit flash drought has devastating impacts on society and the environment. This study explored the historical changes (1960-2015) of the two categories of flash drought over the Pearl River Basin (PRB) in China, and revealed how they would change in the future (2016-2100), by coupling the variable infiltration capacity mode with the global climate model under representative concentration pathway (RCP) 2.6, 4.5, and 8.5 scenarios. Our results indicate that during 1960-2015, the mid-northern PRB has experienced heat wave flash drought frequently while the western PRB suffered from precipitation deficit flash drought. In future, heat wave flash drought under RCP2.6 and 4.5 would occur mostly in the western and eastern PRB. Specifically, heat wave flash drought would become severe under RCP8.5, especially for the eastern PRB. However, precipitation deficit flash drought would be concentrated in the western PRB. Except for the central regions, PRB generally exhibits a significant upward trend in heat wave flash drought under RCP4.5. Under RCP8.5, distinct increases in both categories of flash drought across almost the whole PRB are expected. For precipitation deficit flash drought, only a few regions show significant upward trends under RCP2.6 and 4.5.
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Affiliation(s)
- Jun Li
- School of Civil Engineering and Transportation, South China University of Technology, Guangzhou 510641, China.; Guangdong Engineering Technology Research Center of Safety and Greenization for Water Conservancy Project, Guangzhou 510641, China
| | - Zhaoli Wang
- School of Civil Engineering and Transportation, South China University of Technology, Guangzhou 510641, China.; Guangdong Engineering Technology Research Center of Safety and Greenization for Water Conservancy Project, Guangzhou 510641, China
| | - Xushu Wu
- School of Civil Engineering and Transportation, South China University of Technology, Guangzhou 510641, China.; State Key Laboratory of Water Resources and Hydropower Engineering Science, Wuhan University, Wuhan 430072, China.
| | - Shenglian Guo
- State Key Laboratory of Water Resources and Hydropower Engineering Science, Wuhan University, Wuhan 430072, China
| | - Xiaohong Chen
- Center for Water Resource and Environment, Sun Yat-Sen University, Guangzhou 510275, China
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16
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Fatalism, Climate Resiliency Training and Farmers’ Adaptation Responses: Implications for Sustainable Rainfed-Wheat Production in Pakistan. SUSTAINABILITY 2020. [DOI: 10.3390/su12041650] [Citation(s) in RCA: 28] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/29/2023]
Abstract
Climate change is a severe threat to the agricultural sector in general and to rainfed farming in particular. The aim of this study was to investigate the factors that can potentially affect the adaptation process against climate change. This study focused on wheat farmers and farming systems in the rainfed agroecological zone of Pakistan. Farmers’ data related to climate change fatalism, the availability of climate-specific extension services, socioeconomic and institutional variables, and farm characteristics were collected. A logit model to assess farmers’ decisions to adopt an adaptation measure and a multinomial logit model to assess their choice of various adaptation measures were used. The results showed that fatalistic farmers were unlikely to implement climate change adaptation measures. The variables related to the climate-specific extension services, including farmers’ participation in training on climate-resilient crop farming and the availability of mobile communication-based advisory services, had highly significant and positive impacts on farmers’ decisions and their choice of adaptation measures. Input market access and tractor ownership also had positive and significant impacts on farmers’ decisions to adapt and their choice of adaptation measures. This study highlights the need to improve rainfed-wheat farmers’ education levels to change their fatalistic attitudes towards climate change. Furthermore, government action is needed to provide climate-specific extension services to ensure sustainable production levels that will ultimately lead to food and livelihood security under a changing climate.
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17
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Li J, Wang Z, Lai C. Severe drought events inducing large decrease of net primary productivity in mainland China during 1982-2015. THE SCIENCE OF THE TOTAL ENVIRONMENT 2020; 703:135541. [PMID: 31761360 DOI: 10.1016/j.scitotenv.2019.135541] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/30/2019] [Revised: 11/13/2019] [Accepted: 11/14/2019] [Indexed: 06/10/2023]
Abstract
The analysis of the impact of drought events on terrestrial net primary productivity (NPP) is significant to understand the effects of droughts on regional/global carbon cycling. During the past three decades, terrestrial ecosystems in mainland China have been frequently impacted by drought events. However, quantitative analyses of the variation of NPP induced by droughts are still not enough. Therefore, this study explored the response of NPP to drought events from 1982 to 2015 based on the standardized evapotranspiration deficit index (SEDI) and an NPP dataset obtained from the Carnegie-Ames-Stanford Approach model. We first identified drought events and analyzed the characteristics of drought events using a three-dimensional clustering algorithm. Subsequently, we determined the NPP variations in the drought-affected areas during the droughts and explored the correlation between the NPP variation and the drought characteristics. The results showed that 152 persistent drought events lasting at least 3 months were identified. Most events had durations between 3 and 5 months, and 19 events lasted >9 months. A negative NPP was detected in >60% of the drought-affected areas during long-term (>6 months) and severe (>4 × 106 km2 month) drought events and the total NPP showed a clear decrease during these events. In general, strong drought events reduced the total NPP by >30 TgC in the Northern Region, South Region, Southwest Region, and Northeast Region. The substantial decrease was mainly caused by the NPP anomaly from April to September. The NPP responses to drought events exhibited differences due to different drought characteristics. Although a high proportion of the drought-affected areas experienced a decrease in NPP during most short-term (<5 months) and less severe droughts (<2 × 106 km2 month), the total NPP did not exhibit a large change during these events.
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Affiliation(s)
- Jun Li
- School of Civil Engineering and Transportation, South China University of Technology, Guangzhou 510641, China
| | - Zhaoli Wang
- School of Civil Engineering and Transportation, South China University of Technology, Guangzhou 510641, China; State Key Lab of Subtropical Building Science, South China University of Technology, Guangzhou 510641, China
| | - Chengguang Lai
- School of Civil Engineering and Transportation, South China University of Technology, Guangzhou 510641, China; State Key Lab of Subtropical Building Science, South China University of Technology, Guangzhou 510641, China.
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18
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Yang J, Sun‐Waterhouse D, Xiao Y, He W, Zhao M, Su G. Osteoarthritis‐alleviating effects in papain‐induced model rats of chicken cartilage hydrolysate and its peptide fractions. Int J Food Sci Technol 2019. [DOI: 10.1111/ijfs.14182] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Jingyi Yang
- School of Food Science and Engineering South China University of Technology Guangzhou 510640 China
- Guangdong food Green Processing and Nutrition Regulation Technologies Research Center Guangzhou 510650 China
| | - Dongxiao Sun‐Waterhouse
- School of Food Science and Engineering South China University of Technology Guangzhou 510640 China
- Guangdong food Green Processing and Nutrition Regulation Technologies Research Center Guangzhou 510650 China
| | - Yu Xiao
- School of Food Science and Engineering South China University of Technology Guangzhou 510640 China
- Guangdong food Green Processing and Nutrition Regulation Technologies Research Center Guangzhou 510650 China
| | - Weiwei He
- School of Food Science and Engineering South China University of Technology Guangzhou 510640 China
- Guangdong food Green Processing and Nutrition Regulation Technologies Research Center Guangzhou 510650 China
| | - Mouming Zhao
- School of Food Science and Engineering South China University of Technology Guangzhou 510640 China
- Guangdong food Green Processing and Nutrition Regulation Technologies Research Center Guangzhou 510650 China
| | - Guowan Su
- School of Food Science and Engineering South China University of Technology Guangzhou 510640 China
- Guangdong food Green Processing and Nutrition Regulation Technologies Research Center Guangzhou 510650 China
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Jiang X, Shen W, Bai X. Response of net primary productivity to vegetation restoration in Chinese Loess Plateau during 1986-2015. PLoS One 2019; 14:e0219270. [PMID: 31291307 PMCID: PMC6619688 DOI: 10.1371/journal.pone.0219270] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2019] [Accepted: 06/19/2019] [Indexed: 02/03/2023] Open
Abstract
Land use and land cover change induced by large scale ecological restoration programs has a significant impact on the terrestrial ecosystem carbon cycle, especially on the net primary productivity (NPP) in arid and semi-arid regions. This study investigated the change in NPP caused by the large-scale ecological restoration in the Chinese Loess Plateau (LPR) region from 1986 to 2015 based on land cover datasets and NPP calculated using the Carnegie-Ames-Stanford Approach model. The results indicated that the annual total NPP exhibited a significant uptrend (P < 0.01) throughout the whole vegetation restoration region during the last 30 years, with an annual increase of 0.137 Tg C. A significant abrupt change was detected in 2006 for the annual total NPP series. Over half of the restoration region showed an increase in NPP in the past three decades, however, about 30~40% of the vegetation restoration region exhibited NPP loss before 2006, but subsequently NPP loss was found in only approximately 20% of the study region. Overall, the increase in NPP attributed to the vegetation restoration reached 51.14 Tg C in the past three decades, indicating that these large-scale vegetation restoration programs increased the carbon sequestration capacity of terrestrial ecosystems in the Loess Plateau. The findings of this study improve our understanding of the effects of the green campaign on terrestrial ecosystems.
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Affiliation(s)
- Xueding Jiang
- School of Environmental and Chemical Engineering, Foshan University, Foshan, China
| | - Wen Shen
- Department of Environmental Engineering, School of Environmental Science and Engineering, Guangdong University of Technology, Guangzhou, P. R. China
| | - Xiaoyan Bai
- Department of Environmental Engineering, School of Environmental Science and Engineering, Guangdong University of Technology, Guangzhou, P. R. China
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20
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Spatiotemporal Variability of Actual Evapotranspiration and the Dominant Climatic Factors in the Pearl River Basin, China. ATMOSPHERE 2019. [DOI: 10.3390/atmos10060340] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
Evapotranspiration is a vital component of the land surface process, thus, a more accurate estimate of evapotranspiration is of great significance to agricultural production, research on climate change, and other activities. In order to explore the spatiotemporal variation of evapotranspiration under global climate change in the Pearl River Basin (PRB), in China, this study conducted a simulation of actual evapotranspiration (ETa) during 1960–2014 based on the variable infiltration capacity (VIC) model with a high spatial resolution of 0.05°. The nonparametric Mann–Kendall (M–K) test and partial correlation analysis were used to examine the trends of ETa. The dominant climatic factors impacting on ETa were also examined. The results reveal that the annual ETa across the whole basin exhibited a slight but not significant increasing trend during the 1960–2014 period, whereas a significant decreasing trend was found during the 1960–1992 period. At the seasonal scale, the ETa showed a significant upward trend in summer and a significant downward trend in autumn. At the spatial scale, the ETa generally showed a decreasing, but not significant, trend in the middle and upper stream of the PRB, while in the downstream areas, especially in the Pearl River Delta and Dongjiang River Basin, it exhibited a significant increasing trend. The variation of the ETa was mainly associated with sunshine hours and average air pressure. The negative trend of the ETa in the PRB before 1992 may be due to the significant decrease in sunshine hours, while the increasing trend of the ETa after 1992 may be due to the recovery of sunshine hours and the significant decrease of air pressure. Additionally, we found that the “paradox” phenomenon detected by ETa mainly existed in the middle-upper area of the PRB during the period of 1960–1992.
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21
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Lai C, Zhong R, Wang Z, Wu X, Chen X, Wang P, Lian Y. Monitoring hydrological drought using long-term satellite-based precipitation data. THE SCIENCE OF THE TOTAL ENVIRONMENT 2019; 649:1198-1208. [PMID: 30308891 DOI: 10.1016/j.scitotenv.2018.08.245] [Citation(s) in RCA: 23] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/05/2018] [Revised: 08/17/2018] [Accepted: 08/19/2018] [Indexed: 06/08/2023]
Abstract
Long-term (over 30a) satellite-based quantitative rainfall estimate (SRE) products provide an ideal data source for hydrological drought monitoring. This study mainly explores the suitability of the two long-term SREs, the Precipitation Estimation from Remotely Sensed Information using Artificial Neural Networks-Climate Data Record (PERSIANN-CDR) and the Climate Hazards Group (CHG) Infrared Precipitation with Stations (CHIRPS), for hydrological drought monitoring. A hydrological drought index called the standardized streamflow index (SSI) was used as an example and the Grid-based Xinanjiang (GXAJ) hydrological model was used for streamflow generation of the SREs. A middle size basin in the humid region of south China was selected as case study. The obtained results show that both SREs present acceptable performances for hydrological modeling, and CHIRPS outperformed PERSIANN-CDR. SSIs calculated by the SRE simulations generally fit well with the trend of observation-based on SSI but apparent deviations in drought intensity were also found. In contrast to hydrological modeling, performance of the SRE-based SSI showed almost no change after model recalibration. Both SREs generally present acceptable classification accuracy but tended to underestimate the levels of drought types. Both SREs accurately captured the beginning, end, and duration of this drought event; however, several deviations were found in severity and intensity estimation of the drought event. In general, both SREs are suitable for hydrological drought monitoring. Although the CHIRPS generally presented better performance, the PERSIANN-CDR is still adequate for hydrological drought monitoring.
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Affiliation(s)
- Chengguang Lai
- School of Civil Engineering and Transportation, South China University of Technology, Guangzhou 510641, China
| | - Ruida Zhong
- School of Civil Engineering and Transportation, South China University of Technology, Guangzhou 510641, China; Center for Water Resources and Environment Research, SUN Yat-sen University, Guangzhou, 510275, China
| | - Zhaoli Wang
- School of Civil Engineering and Transportation, South China University of Technology, Guangzhou 510641, China.
| | - Xiaoqing Wu
- South China Institute of Environment Sciences, Ministry of Environment Protection of PRC, Guangzhou 510535, China
| | - Xiaohong Chen
- Center for Water Resources and Environment Research, SUN Yat-sen University, Guangzhou, 510275, China
| | - Peng Wang
- Department of Ecology, Jinan University, Guangzhou, 510632, China
| | - Yanqing Lian
- The Prairie Research Institute, University of Illinois at Urbana-Champaign, 2204 Griffith Drive, Champaign, IL 61820, USA
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22
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Drought-Induced Reduction in Net Primary Productivity across Mainland China from 1982 to 2015. REMOTE SENSING 2018. [DOI: 10.3390/rs10091433] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Terrestrial net primary productivity (NPP) plays an essential role in the global carbon cycle as well as for climate change. However, in the past three decades, terrestrial ecosystems across mainland China suffered from frequent drought and, to date, the adverse impacts on NPP remain uncertain. This study explored the spatiotemporal features of NPP and discussed the influences of drought on NPP across mainland China from 1982 to 2015 using the Carnegie Ames Stanford Application (CASA) model and the standardized precipitation evapotranspiration index (SPEI). The obtained results indicate that: (1) The total annual NPP across mainland China showed an non-significantly increasing trend from 1982 to 2015, with annual increase of 0.025 Pg C; the spring NPP exhibited a significant increasing trend (0.031 Pg C year−1, p < 0.05) while the summer NPP showed a higher decreasing trend (0.019 Pg C year−1). (2) Most areas of mainland China were spatially dominated by a positive correlation between annual NPP and SPEI and a significant positive correlation was mainly observed for Northern China; specific to the nine sub-regions, annual NPP and SPEI shared similar temporal patterns with a significant positive relation in Northeastern China, Huang-Huai-Hai, Inner Mongolia, and the Gan-Xin Region. (3) During the five typical drought events, more than 23% areas of mainland China experienced drought ravage; the drought events generally caused about 30% of the NPP reduction in most of the sub-regions while the NPP in the Qinghai-Tibet Plateau Region generally decreased by about 10%.
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GIS-Based Random Forest Weight for Rainfall-Induced Landslide Susceptibility Assessment at a Humid Region in Southern China. WATER 2018. [DOI: 10.3390/w10081019] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
Landslide susceptibility assessment is presently considered an effective tool for landslide warning and forecasting. Under the assessment procedure, a credible index weight can greatly increase the rationality of the assessment result. Using the Beijiang River Basin, China, as a case study, this paper proposes a new weight-determining method based on random forest (RF) and used the weighted linear combination (WLC) to evaluate the landslide susceptibility. The RF weight and eight indices were used to construct the assessment model. As a comparison, the entropy weight (EW) and weight determined by analytic hierarchy process (AHP) were also used, respectively, to demonstrate the rationality of the proposed weight-determining method. The results show that: (1) the average error rates of training and testing based on RF are 18.12% and 15.83%, respectively, suggesting that the RF model can be considered rational and credible; (2) RF ranks the indices elevation (EL), slope (SL), maximum one-day precipitation (M1DP) and distance to fault (DF) as the Top 4 most important of the eight indices, occupying 73.24% of the total, while the indices runoff coefficient (RC), normalized difference vegetation index (NDVI), shear resistance capacity (SRC) and available water capacity (AWC) are less consequential, with an index importance degree of only 26.76% of the total; and (3) the verification of landslide susceptibility indicates that the accuracy rate based on the RF weight reaches 75.41% but are only 59.02% and 72.13% for the other two weights (EW and AHP), respectively. This paper shows the potential to provide a new weight-determining method for landslide susceptibility assessment. Evaluation results are expected to provide a reference for landslide management, prevention and reduction in the studied basin.
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Quantitative Evaluation of the Impact of Climate Change and Human Activity on Runoff Change in the Dongjiang River Basin, China. WATER 2018. [DOI: 10.3390/w10050571] [Citation(s) in RCA: 31] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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